Re: [PATCH] xfs: Drop setting redundant PF_KSWAPD in kswapd context

From: Dave Chinner
Date: Thu Aug 24 2017 - 20:02:12 EST


On Thu, Aug 24, 2017 at 12:56:35PM +0200, Michal Hocko wrote:
> On Thu 24-08-17 16:12:47, Anshuman Khandual wrote:
> > xfs_btree_split() calls xfs_btree_split_worker() with args.kswapd set
> > if current->flags alrady has PF_KSWAPD. Hence we should not again add
> > PF_KSWAPD into the current flags inside kswapd context. So drop this
> > redundant flag addition.
>
> I am not familiar with the code but your change seems incorect. The
> whole point of args->kswapd is to convey the kswapd context to the
> worker which is obviously running in a different context. So this patch
> loses the kswapd context.

Yup. That's what the code does, and removing the PF_KSWAPD from it
will break it.

Cheers,

Dave.
--
Dave Chinner
david@xxxxxxxxxxxxx